Double contact electric socket



Oct. 23, 1934. J RQPER 1,978,116

DOUBLE CONTACTI ELECTRIC SOCKET Fild Nov. 23, 1953 BEND LINE JOHN M. PQPER INVENTOR v vl b/ g. 5- W ATTORNEY LUNITED STATES Patented Oct. 23, 1 934 PATENT OFFICE.

(Granted under the mini March 3, 1883, as amended April 30, 1928; 3700. G. 757) This invention relates to a double contact electric socket and has for an object to provide :an improved electrical socket especially foruse on aircraft both of the lighter and heavier thanair type where the economy of space and weight are desirable features and relates more particularly to the adaptation to a double contactof theinvention shown inthe application Serial No. 699,426 filed November 27, 1933, concurrently herewith on a single contact electric socket by the same inventor.

A further object of this invention is to provide an electrical socket especially adapted for holding electrical lamps of the bayonet type for use on vehicles of all descriptions, both vehicles used inthe air, on the ground, on the water, and under the water. i a A still further object of this invention is to provide a lamp socket occupying a minimum amount of. space and weight which will be especiallytuseful on vehicles such as aircraft, and more particularly on the wing surfaces and edges, so as to receive and hold a lamp in such positions without seriously affecting the aerodynamic characteristics of the wing surfaces.

A stillfurther object of. this invention is to provide an electrical socket wherein the terminalis fixedly secured to the conductor member and the lamp is yieldably held in contact with 9 the "terminal rather than the conventional type Fig. 1 is a top plan view of the assembled 4 socket a Fig. 2 is a cross section on the line 22 of Fig. 1;

\Fig. 3is a cross section on the-line 3--3 of Fig. 1; 1 Fig. 4 is a development of the socket shell blank; 1 i

Fig. 5 is a top plan view of the socket hous- Fig. 6 is a cross section on line 6--6 of Fig. 5; Fig. 7 is a top plan view of the terminal assembly;

Fig. 8 is a side elevation of the terminal assembly per se; and

Fig. 9 is a cross section of the terminal assembly taken on line 9-9 of Fig. 7.

There is shown at 10 the assembled socket con-. stituting this invention. This socket 10 comprises terminal assembly 11 consisting of two terminal inserts 12 about thefianges of which are molded an insulator 13, this insulator 13 being formed by molding an insulating material such as rubber, a phenolic condensation product commonly known as bakelite' or such like thereabout according to'the shape shown on the drawing. Each terminal insert is provided with a terminal hump 14 projecting externallyof the molding 13 and a fan-shaped section which is left bare of molding on the upper side, which section includes an aperture 15 therethrough leading toa corree sponding aperture 16 left in the molding on the bottom of the terminal assembly. The two terminal inserts are spaced from each other within the terminalassembly 11 by insulation molded therebetween so that theterminal humps 14 of each insert makes contact with the separate con-.- tacts of a double contact electric lamp 17. The terminal assembly 11 is held on a reinforcing terminal support 18 having a pair of opposite fingers 19 bent over into opposite slots 20 pro vided in the top of the insulation 13. The terminal support 18 is apertured asat20 to'permit the passage therethrough of lead {wires 21, each lead wire 21 passing through the aperture 15 i in the terminal insert 12 and spread over the fan-shaped section which is bare of insulation and secured thereto as by solder, the lead wires 21 being received in the conduit 22. As will be apparent, the lead: wires 21 in the terminalv assembly 11 thus provided are securely fastened thereto and there is no possibility of corrosion or accident interfering with the completion of the circuit from the leads 21 to the contact humps 14. The terminal assembly 11 is placed in a cap nut 23 which is apertured to permit the conduit 22 to pass therethrough. This cap nut 23 is internallythreaded as at 24. Threaded into the cap nut 23 is a socket housing 25 which contains a yiel'dable compression spring 26 and a socket shell 27. g

This socket shell 27, a development of which is shown in Fig, 4, iscylindrical in shape and has a projecting flange or base 28 at the base thereof. This socket shell 2'7 is provided with a pair of bayonet slots 29 and 30 having recesses 31 separated from the entrance slots 32 by a boss '33 to cooperate with the holding pins on the conventional double contact lamp 1'7 inserted therein. The bayonet slot 29 is connected to a recess slot 34, a bendable tab separating the slot 29 from the slot 34, this tab 35 and slot 30 cooperating with a boss 36 on the internally projecting rim or flange 37 of the housing 25 which enters the bayonet slot 29 until it reaches the bent tab 35. The socket shell 27 and housing 25 are then rotated relative to each other causing the boss 36 to enter the slot 3 1. A suitable tool then placed in the socket shell ,26 presses.

the tab 35 into the cylindrical plane of the socket shell thereby closing oii the slot 34 and preventing the separation of the shell 2.? from the. housing 25. With the shell 2'? and housing 25 thus assembled and locked against separation the housing 21 is then threaded into the internal threads 34 of the cap nut 23, the finger 19- of the terminal support 18 entering the slots 38 in the housing 21 thus properly positioning the terminal humps 14 relative to the terminal contacts on the double contact lamp 1'7 placed within the assembled housing.

In operation the conventional double contact bulb 1'7 is placed in the socket 10 by means of the bayonet slots 29 and 30, being held in the recess 31 by the fact that the compression spring 26 yields after the lamp is inserted, and permits the shell 2'7 toride upwardly within the limits of the movement of the boss 36 and the slot 34. With this construction it will be observed that the terminal assembly 11 is securely held to the wiring 21 of the conduit 22, the electric lamp is held in the socket shell 27 and is held yieldably against the contact hump of terminal 11. The connection between the wiring 21 of conduit 22 may be made as secure as possible as already described, there being no yielding parts therebetween as in the conventional plunger type, and thus no possible corrosion of the within the plug contact'preventing the completion of the circuit from the conduit to the lamp. Further, it is impossible to pull conduit 22 away from the terminal 11 due to the elimination of. any yielding parts therebetween.

It will be understood that the above description and accompanying drawing comprehend only the general and preferred embodiment of my invention and that various changes in construction, proportion and arrangement of parts may be made within the scope of the appended claims without sacrificing any of the advantages of my invention.

The invention described herein may be manufactured and used by or for the Government or the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

I claim:

1. A lamp socket comprising an apertured cap nut, an insulated double contact terminal member in said apertured cap nut, a conduit to said terminal extending through the aperture of said nut, a lamp socket assembly threadedly secured in said cap nut, said lamp socket assembly comprising an inner socket shell, an outwardly flanged base on said shell, a socket housing, an inwardly flanged rim on said socket housing, said rim being apertured, and a compression spring,

said socket shell being placed within said socket housing and saidcompression spring being secured between said housing rim and said shell base, said insulated double contact terminal member comprising a pair of terminal inserts and insulation molded about and securing said inserts therein in spaced relation, a contact on each insert projecting through said insulation, each terminal insert having an aperture extending therethrough and said aperture also extending through said insulation, each terminal insert being bare of insulation about said aperture for receiving and securing a lead wire thereto, an apertured terminal support for said terminal assembly within said socket assembly, a pair of opposite bent fingers on said support, said molded insulation of said terminal assembly having a pair of opposite slots therein, said slots receiving said bent fingers therein, a pair of slots in said socket housing, said bent fingers also entering said socket housing slots to more properly position said terminal contacts in relation to said socket assembly.

2'. A lamp socket comprising an apertured cap nut, an insulated terminal member in said apertured cap nut, a conduit to said terminal extending through the aperture of said nut, a lamp socket assembly threadedly secured in said cap nut, said lamp socket assembly comprising an inner socket shell, an outwardly flanged base on said shell, a socket housing, an inwardly flanged rirnon said socket housing, said rim being apertured, an internally projecting boss on said housing rim, a compression spring, said socket shell being placed within said socket housing, said compression spring being secured between said housing rim and said shell flange, said socket shell having a pair of bayonet joint slots extending to the edge thereof and an internal slot connected to one of said bayonet slots, a bendable tab separating said internal slot from said bayonet slot, said internal slot being adapted to receive said housing rim boss therein, and to lock said 1 boss therein by having said bendable taper placed in the cylindrical plane of said shell, said insulated terminal comprising a washer-like conductor member, an insulation molded about the periphery of said washer-like conductor member, a hump formed in the center of said washer-like member and extending beyond the surface of the molded insulation, said hump providing the terminal contact, an apertured terminal support for said terminal assembly within said socket shell, a pair of opposite bent fingers on said support, said molding of said terminal assembly having a pair of opposite slots therein, said slots receiving said bent fingers therein, said socket housing having a pair of slots therein, said bent fingers entering said socket housing slots to more properly position said terminal hump contacts in relation to said socket assembly.

'3. In a double contact lamp socket, a lea-d contact member comprising a disc like insulation member, a pair of spaced apart insert members molded therein, each insert member being provided with an aperture therethrough and through said molded insulation, a section of said insert about saidaperture being bare on the lamp side thereon, the lead wire extending through said aperture, the end of said lead wire being soldered to said bare section of insert, and a hump on said insert extending externally above said insulation and providing a lamp contact member.

JOHN M. ROPER. v 

